We have completed a genome scan for type 2 diabetes and related phenotypes at an average resolution of 10cM on 2401 individuals. In all, more than 1.3 million genotypes have been generated with an overall error rate of 0.11 percent. The maximum multipoint weighted lod score for diabetes is 2.15 on chromosome 20 at 69.5 cM from the most p telomeric marker. Additional multipoint lod scores of 1.99 at 17.5 cM and 1.90 at 51.5 cM are also seen on this chromosome. The HNF4alpha gene (MODY1, approximately 65 cM) has been excluded as a major contributor to the maximum lod score. Only one other region, that on chromosome 11, has a multipoint weighted lod score greater than 1 (1.18 at 79.5 cM). Stratification analysis based on a diabetes-related phenotype gives significant linkage results (p<0.05) for diabetes on chromosomes 10, 14 and 22. We have also received, diluted and organized 2916 DNA samples from extended family members and from a new replication sample. Association analyses at an average resolution of 2 cM will be conducted on chromosome 20 using the information in the combined dataset according to birthplaces of parents or grandparents in Finland. We then plan to pursue positional cloning of diabetes-related genes on chromosome 20 after narrowing down areas of linkage to manageable intervals.